Modified Embedded Atom Method (MEAM) potential for hydrocarbons (C/H)

These MEAM parameters for elements C and H as well as the diatomic CH are appropriate for energy minimization and reactive molecular dynamics simulations of SATURATED hydrocarbons, where all carbon atoms have the sp3 hybridization (single C-C bonds).[1] At the current state, MEAM cannot handle unsaturated compounds with great accuracy. Furthermore, these C and H parameters are not appropriate for diamond and graphite systems. Modification of the MEAM potential to include unsaturated C-C bonds, i.e., double and triple bonds, as well as its parameterization for elements oxygen and nitrogen is ongoing work.

For the first time, MEAM can be used to simulate hydrocarbons and hydrocarbon/metal systems, since it has a large parameter database for major metals in the periodic table of elements. Since MEAM is a reactive potential, it can also be used to simulate fracture and fatigue in hydrocarbon-based polymers, such as polyethylene and polypropylene and their composites with nanometals as well as polymer/metal interfaces.

MEAM can be run in both DYNAMO and LAMMPS software packages. The C, H, and CH parameters are given below for both DYNAMO and LAMMPS and give equivalent results.

MEAM parameters for LAMMPS:

The following two parameter sets should be copied and pasted into two separate text files named library.meam and CH.meam, respectively, in your working directory.